Labrador-Island Link aces the 700-MW test, paving the way for Muskrat Falls completion

The second and final 700-megawatt test of the Labrador-Island Link has been completed successfully, potentially opening the door for thelong-delayed final commissioning of the Muskrat Falls project.

Newfoundland and Labrador Hydro says the system is performing as expected with no outagesand they will continue monitoring the system at 675 megawatts for another 12 hours to complete the test.

It's a major improvement on the last time the 700-megawatt test was attempted, in November. That test resulted in outages for around 60,000 customers across Newfoundland.

N.L. Hydro says that was due to a bug in the software that runs the Labrador-Island Link, a 1,100-kilometre high-voltage transmission line from the Muskrat Falls generating station to the Soldiers Pond converter station just outside St. John's.

The 700-megawatt test is designed to run the system at a higher-than-normal power level for a sustained period. According to the company, that will determine whether the link's software is working correctly.

If the new tests had failed, it might have meant adding another year to an already five-years-delayed project, as they can only be completed during peak demand periods in winter, under cold weather conditions.

The link'ssoftware had become a major hurdle delaying final commissioning of the hydroelectric project, with GE Grid Solutions struggling to fine-tune the software over a period of several years, involving multiple tests and several upgrades to the programming as they worked.

The generating station itself has been running since the end of 2021 and had its first full year of operation in 2022 with little incident.

Last month, N.L. Hydro president and CEO Jennifer Williams told CBC News she was optimistic about the tests and the completion of the project.

"I feel very good about this asset and I feel very good about the people that are running it. And I do feel a bit defensive about that sometimes, 'cause I want those folks to know they're producing an excellent product every day out of that plant and that line," said Williams.

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